The invention relates to the technical field of load handling equipment, in particular public works machines having skips, buckets or other means for scraping, extracting, shifting materials and others for their removal from a given place to other operating stations using the said machines.
The prior art teaches how to place wear parts on the cutting blade of various buckets, skips and other receptacles, for their penetration capacity and their protection. “Adapter-supports” are fixed to the cutting blades, having a profiled nose, while the wear parts are teeth or shields which are positioned on the adapter-support by a precise, temporary linkage to allow their replacement after wear. Various technologies are available, like those developed by the applicants themselves.
The linkage is provided in most cases by keying, the tooth or the shield and the adapter support being profiled to accommodate the key. This may be metallic with an exclusively mechanical assembly, or with the incorporation of a support element of elastic material, which may also be in the form of a sleeve preformed or prepared in situ by pouring resin.
Also known is the design of keys called “sandwich” designed with two components receiving an elastic lining. In most cases, the assembly and disassembly of the keys take place by the action of striking tools.
Thus, with regard to the prior art, mention can be made of the patents EP 0618.334, WO 2004/035945, and EP 1.048.792. To be efficient, the keying devices must guarantee a firm link of the elements that they combine, which makes their assemblies and disassemblies often difficult with the risk of injury to the operators.
In the case of keyings, not requiring the use of striking tools, special and difficult equipment is necessary, above all for dismantling. According to the known devices, these keyings are complicated, excessively mechanical, and intolerant of the presence of materials detrimental to their operation.
The approach of the applicants was therefore to reflect on a novel design of the key linkage device allowing the abandonment of striking operations, both for assembling and disassembling the teeth, thereby guaranteeing the safety of the operators, while ensuring the performance of the tooth-adapter link by a simple, readily accessible system.
A further object of the invention was to provide a device not demanding geometrical rigour in the relative positioning of the tooth with regard to the adapter.
These objects and others will clearly appear from the rest of the description.